org.bedework.util.xml

Class XmlUtil

java.lang.Object

org.bedework.util.xml.XmlUtil

All Implemented Interfaces:

Serializable

public final class XmlUtil
extends Object
implements Serializable

Utility routines associated with handling xml

Author:

Mike Douglass douglm rpi.edu

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	XmlUtil.CheckStringResult Result from checking string

Field Summary

Fields

Modifier and Type	Field and Description
static int	xmlError Errors occurred during tidy
static int	xmlMissing Field has no value
static int	xmlNotXml The parameter was untagged text
static int	xmlOk Field is tidied
static int	xmlTidyException Exception when tidied
static int	xmlTidyNull Xml became null when tidied
static int	xmlUntidy Xml is (probably) valid but not tidied

Constructor Summary

Constructors

Constructor and Description
XmlUtil()

Method Summary

Modifier and Type	Method and Description
static void	checkString(String id, String val, XmlUtil.CheckStringResult crs, boolean emptyOk) This does everything tidyString does with the addition that it adjusts the result to indicate something about the original string.
static QName	fromNode(Node nd) Return a QName for the node
static String	getAttrVal(Element el, String name) Return the value of the named attribute of the given element.
static String	getAttrVal(NamedNodeMap nnm, String name) Return the attribute value of the named attribute from the given map.
static String	getElementContent(Element el) Return the content for the current element.
static String	getElementContent(Element el, boolean trim) Return the content for the current element.
static List<Element>	getElements(Node nd) All the children must be elements or white space text nodes.
static Element[]	getElementsArray(Node nd)
static String	getOneNodeVal(Node el) Get the value of an element.
static String	getOneNodeVal(Node el, String name) Get the value of an element.
static Node	getOneTaggedNode(Node el, String name) Get the single named element.
static Element	getOnlyElement(Node nd)
static String	getReqAttrVal(Element el, String name) Return the required value of the named attribute of the given element.
static String	getReqOneNodeVal(Node el) Get the value of an element.
static String	getReqOneNodeVal(Node el, String name) Get the value of an element.
static Boolean	getYesNoAttrVal(NamedNodeMap nnm, String name) The attribute value of the named attribute in the given map must be absent or "yes" or "no".
static boolean	hasChildren(Element el) See if this node has any children
static boolean	hasContent(Element el) Return true if the current element has non zero length content.
static boolean	isEmpty(Element el) See if this node is empty
static boolean	nodeMatches(Node nd, QName tag) See if node matches tag
static int	numAttrs(Node nd)
static void	setElementContent(Node n, String s) Replace the content for the current element.
static void	tidyString(String id, String val, XmlUtil.CheckStringResult crs) Given a string return a tidied form of the string.
static String	tidyXML(String id, String val, PrintWriter err) Given a string return a tidied form of the string.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

xmlOk

public static final int xmlOk

Field is tidied

See Also:

Constant Field Values

xmlMissing

public static final int xmlMissing

Field has no value

See Also:

Constant Field Values

xmlUntidy

public static final int xmlUntidy

Xml is (probably) valid but not tidied

See Also:

Constant Field Values

xmlError

public static final int xmlError

Errors occurred during tidy

See Also:

Constant Field Values

xmlTidyNull

public static final int xmlTidyNull

Xml became null when tidied

See Also:

Constant Field Values

xmlNotXml

public static final int xmlNotXml

The parameter was untagged text

See Also:

Constant Field Values

xmlTidyException

public static final int xmlTidyException

Exception when tidied

See Also:

Constant Field Values

Constructor Detail

XmlUtil

public XmlUtil()

Method Detail

tidyString

public static void tidyString(String id,
                              String val,
                              XmlUtil.CheckStringResult crs)

Given a string return a tidied form of the string. Throws an exception if the xml tidy method does so.

Take care, certain forms of input result in no output. Note that we watch specifically for a line consisting of a single new line character.

We also check for a string that is just text with no markup. This check is rather simple.

If the first non-whitespace character is not > we assume simple text input and optionally attempt to tag it.

This check is suppressed if tagUntagged = false.

Parameters:

id - String to identify input

val - String to tidy

crs - Object to hold results

checkString

public static void checkString(String id,
                               String val,
                               XmlUtil.CheckStringResult crs,
                               boolean emptyOk)

This does everything tidyString does with the addition that it adjusts the result to indicate something about the original string.

if emptyOk is false and the result is null the status is xmlNull otherwise a null value is considered OK.

We also check for the value changing. A change indicates some tidying took place so we return xmlUntidy.

Parameters:

id - String to identify input

val - String to tidy

crs - Object to hold results

emptyOk - True if empty text is not special

tidyXML

public static String tidyXML(String id,
                             String val,
                             PrintWriter err)
                      throws Exception

Given a string return a tidied form of the string. Throws an exception if the xml tidy method does so.

Take care, certain forms of input result in no output. Note that we watch specifically for a line cosisting of a single new line character.

We also check for a string that is just text with no markup. This check is rather simple.

If the first non-whitespace character is not > we assume simple text input and optionally attempt to tag it.

Parameters:

id - String to identify input

val - String to tidy

err - An error output stream

Returns:

String tidied result.

Throws:

Exception - When tidying fails.

getOneTaggedNode

public static Node getOneTaggedNode(Node el,
                                    String name)
                             throws SAXException

Get the single named element.

Parameters:

el - Node

name - String tag name of required node

Returns:

Node node value or null

Throws:

SAXException

getOneNodeVal

public static String getOneNodeVal(Node el,
                                   String name)
                            throws SAXException

Get the value of an element. We expect 0 or 1 child nodes. For no child node we return null, for more than one we raise an exception.

Parameters:

el - Node whose value we want

name - String name to make exception messages more readable

Returns:

String node value or null

Throws:

SAXException

getOneNodeVal

public static String getOneNodeVal(Node el)
                            throws SAXException

Get the value of an element. We expect 0 or 1 child nodes. For no child node we return null, for more than one we raise an exception.

Parameters:

el - Node whose value we want

Returns:

String node value or null

Throws:

SAXException

getReqOneNodeVal

public static String getReqOneNodeVal(Node el,
                                      String name)
                               throws SAXException

Get the value of an element. We expect 1 child node otherwise we raise an exception.

Parameters:

el - Node whose value we want

name - String name to make exception messages more readable

Returns:

String node value

Throws:

SAXException

getReqOneNodeVal

public static String getReqOneNodeVal(Node el)
                               throws SAXException

Get the value of an element. We expect 1 child node otherwise we raise an exception.

Parameters:

el - Node whose value we want

Returns:

String node value

Throws:

SAXException

getAttrVal

public static String getAttrVal(Element el,
                                String name)
                         throws SAXException

Return the value of the named attribute of the given element.

Parameters:

el - Element

name - String name of desired attribute

Returns:

String attribute value or null

Throws:

SAXException

getReqAttrVal

public static String getReqAttrVal(Element el,
                                   String name)
                            throws SAXException

Return the required value of the named attribute of the given element.

Parameters:

el - Element

name - String name of desired attribute

Returns:

String attribute value

Throws:

SAXException

getAttrVal

public static String getAttrVal(NamedNodeMap nnm,
                                String name)

Return the attribute value of the named attribute from the given map.

Parameters:

nnm - NamedNodeMap

name - String name of desired attribute

Returns:

String attribute value or null

getYesNoAttrVal

public static Boolean getYesNoAttrVal(NamedNodeMap nnm,
                                      String name)
                               throws SAXException

The attribute value of the named attribute in the given map must be absent or "yes" or "no".

Parameters:

nnm - NamedNodeMap

name - String name of desired attribute

Returns:

Boolean attribute value or null

Throws:

SAXException

numAttrs

public static int numAttrs(Node nd)

Parameters:

nd -

Returns:

int number of attributes

getElements

public static List<Element> getElements(Node nd)
                                 throws SAXException

All the children must be elements or white space text nodes.

Parameters:

nd -

Returns:

Collection element nodes. Always non-null

Throws:

SAXException

getElementContent

public static String getElementContent(Element el,
                                       boolean trim)
                                throws SAXException

Return the content for the current element. All leading and trailing whitespace and embedded comments will be removed.

This is only intended for an element with no child elements.

Parameters:

el -

trim - true to trim surrounding white-space

Returns:

element content

Throws:

SAXException

setElementContent

public static void setElementContent(Node n,
                                     String s)
                              throws SAXException

Replace the content for the current element.

Parameters:

n - element

s - string content

Throws:

SAXException

getElementContent

public static String getElementContent(Element el)
                                throws SAXException

Return the content for the current element. All leading and trailing whitespace and embedded comments will be removed.

This is only intended for an element with no child elements.

Parameters:

el -

Returns:

element content

Throws:

SAXException

hasContent

public static boolean hasContent(Element el)
                          throws SAXException

Return true if the current element has non zero length content.

Parameters:

el -

Returns:

boolean

Throws:

SAXException

hasChildren

public static boolean hasChildren(Element el)
                           throws SAXException

See if this node has any children

Parameters:

el -

Returns:

boolean true for any child elements

Throws:

SAXException

isEmpty

public static boolean isEmpty(Element el)
                       throws SAXException

See if this node is empty

Parameters:

el -

Returns:

boolean true for empty

Throws:

SAXException

getElementsArray

public static Element[] getElementsArray(Node nd)
                                  throws SAXException

Parameters:

nd -

Returns:

element array from node

Throws:

SAXException

nodeMatches

public static boolean nodeMatches(Node nd,
                                  QName tag)

See if node matches tag

Parameters:

nd -

tag -

Returns:

boolean true for match

fromNode

public static QName fromNode(Node nd)

Return a QName for the node

Parameters:

nd -

Returns:

boolean true for match

getOnlyElement

public static Element getOnlyElement(Node nd)
                              throws SAXException

Parameters:

nd -

Returns:

only child node

Throws:

SAXException - if not exactly one child elemnt